1 files changed, 1 insertions, 0 deletions
diff --git a/diff.h b/diff.h
index 9b2e1e62bb..32b4780173 100644
--- a/diff.h
+++ b/diff.h
@@ -77,6 +77,7 @@ extern int diff_scoreopt_parse(const char *opt);
 #define DIFF_SETUP_USE_CACHE		2
 #define DIFF_SETUP_USE_SIZE_CACHE	4
 
+extern int git_diff_config(const char *var, const char *value);
 extern void diff_setup(struct diff_options *);
 extern int diff_opt_parse(struct diff_options *, const char **, int);
 extern int diff_setup_done(struct diff_options *);